1. Field of Invention
The present invention relates to a photoelectric detection technology, and more particularly to a black silicon based metal-semiconductor-metal photodetector and method of manufacture thereof.
2. Description of Related Arts
Silicon is an important semiconductor material, and currently also a main material used in the microelectronics integrated circuit process, and plays a very important role in the very large scale integrated circuit (VLSI). Compared with other compound optoelectronic devices, the optoelectronic devices and optoelectronic integrated circuits manufactured by the mature standard integrated circuit (IC) process using silicon as a basic material, will have a great advantage, however, the research on the silicon-based photodetector still has no great breakthrough at present. When the light wave is incident on the surface of the silicon-based optoelectronic device, the reflected light energy can be about 30%, so the responsivity of the silicon-based metal-semiconductor-metal photodetector (MSM-PD) is only about 0.2 A/W, and its quantum efficiency is very low and about 0.34. Therefore, the key issue to be resolved in the silicon-based MSM-PD is still the low sensitivity.
Black silicon is a microstructure layer on the surface of silicon. The existence of the microstructure layer can significantly improve the optoelectronic property of silicon material, so it has become the hot topic of research in recent years. For the preparation of the microstructure layer on the surface of silicon, many methods can be used, which include an electrochemical method, reaction ion etching (RIE) and laser chemistry method. The laser chemistry method for preparing black silicon material can not only obtain regular micro-needle arrays on the surface of silicon, increase the absorption coefficient of the material, but also introduce high doping impurities, and widen the optical absorption scope of the material, thus showing the wide application prospects of black silicon material in the optoelectronics field.
Therefore, a black silicon layer is obtained by the ion implantation and preparation of the surface microstructure. Furthermore, a black silicon based metal-semiconductor-metal photodetector is prepared, and it has a wide spectral response range and high responsivity.